[binutils-gdb] [gdb/testsuite, Tcl 9.0] Fix use of deprecated trace variable subcommand

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=ef7727ae62774ae4298008937e133c614b8eeaec

commit ef7727ae62774ae4298008937e133c614b8eeaec
Author: Tom de Vries <[email protected]>
Date:   Fri Mar 20 10:13:27 2026 +0100

    [gdb/testsuite, Tcl 9.0] Fix use of deprecated trace variable subcommand
    
    With Tcl 9.0, we get:
    ...
    bad option "variable": must be add, info, or remove
        while executing
    "trace variable "boards_dir" w append_gdb_boards_dir"
        (file "lib/append_gdb_boards_dir.exp" line 48)
    ...
    
    The trace subcommand "trace variable <name> <ops> <command>" [1]:
    - is equivalent to "trace add variable <name> <ops> <command>"
    - is for backwards compatibility,
    - uses "an older syntax in which array, read, write, unset are replaced by a,
      r, w and u respectively",
    - has an ops argument which is "not a list, but simply a string concatenation
      of the operations", and
    - is "deprecated and will likely be removed in a future version of Tcl".
    
    Fix this by using "trace add variable":
    ...
    -trace variable "boards_dir" w append_gdb_boards_dir
    +trace add variable "boards_dir" {write} append_gdb_boards_dir
    ...
    
    Approved-By: Tom Tromey <[email protected]>
    
    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33948
    
    [1] https://www.tcl-lang.org/man/tcl8.6/TclCmd/trace.htm#M27

Diff:
---
 gdb/testsuite/lib/append_gdb_boards_dir.exp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/testsuite/lib/append_gdb_boards_dir.exp b/gdb/testsuite/lib/append_gdb_boards_dir.exp
index fb756409065..8984744ab86 100644
--- a/gdb/testsuite/lib/append_gdb_boards_dir.exp
+++ b/gdb/testsuite/lib/append_gdb_boards_dir.exp
@@ -45,4 +45,4 @@ proc append_gdb_boards_dir { name1 name2 op } {
     }
     lappend boards_dir "${gdb_boards_dir}"
 }
-trace variable "boards_dir" w append_gdb_boards_dir
+trace add variable "boards_dir" {write} append_gdb_boards_dir